Winemakers often plant rosebushes among their grapevines. It's no aesthetic flourish: Vintners watch those roses for early warnings of disease or pests. Biosentinel plants are genetically engineered crops meant to provide the same kinds of warnings for farmers of all kinds. Scientists at the Australian research institute CAMBIA are trying to come up with nonfood strains of rice, whose simple genome makes it relatively easy to manipulate, that will send a signal (e.g., emit a pungent smell or turn color) in response to danger signs. And it's not just the tool (which is still a few years from fruition) that could be revolutionary: CAMBIA founder and biologist Richard Jefferson is in the vanguard of an open-source biotech movement in which innovations are shared instead of locked into patents. "It's not a matter of providing biotech solutions for the Third World," Jefferson says. "It's putting the farmer in the driver's seat." --Jia Lynn Yang